Shearing machine

A shearing machine, comprising:

• a frame;
• a work-table provided integrally on the frame;
• a lower blade detachably fixed to the work-table at the level of the work-table;
• an upper blade;
• a ram supported on said frame for vertical movement with respect to said lower blade, said ram holding the upper blade for performing shearing operations in cooperation with the lower blade;
• a drive shaft supported on said frame;
• an eccentric fixed on said drive shaft connected with said ram for driving said ram;
• fluid motors for holding down a work-sheet provided at a front portion of the frame;
• pump means connected by a passage to the fluid motors wherein said pump means comprises;
• first means for supplying a large amount of flow under low pressure to the pump means;
• second means for supplying a small amount of flow under high pressure;
• said first flow supplying means comprising a first cylinder and a first piston and first resilient means biasing said first piston in a first direction relative to said first cylinder, a cam fixed on said drive shaft engaging said first piston for driving said first piston;
• and
• means for damping pressure surges, said damping means comprising second resilient means arranged to coact with said first piston for biasing said first piston in a second direction opposite said first direction.

A shearing machine, comprising:

• a frame;
• a work-table provided integrally on the frame;
• a lower blade detachably fixed to the work-table at the level of the work-table on the frame;
• an upper blade;
• a ram supported on said frame for vertical movement with respect to said lower blade, said ram holding the upper blade for performing shearing operations in cooperation with the lower blade;
• rails supported on the ram at the back of the upper blade;
• carrier means provided on said rails for horizontal movement along said rails;
• means for moving said rails, said carrier means being pivotably connected to said moving means;
• a back gauge supported on said carrier means at the level of the work-table for setting the dimension of the work-piece to be sheared;
• and
• cam means mounted on said rails for pivoting the carrier means and the back gauge away from the level of the work-table such that the work-piece is free to move horizontally on the work-table without engaging the back gauge.

A shearing machine comprising:

• a frame;
• a work-table provided integrally on the frame;
• a lower blade detachably fixed to the work-table;
• an upper blade;
• a ram supported on said frame for vertical movement with respect to said lower blade, said ram holding the upper blade for performing shearing operations in cooperation with the lower blade;
• and
• hold-up means supported in said frame beneath said work-table, said hold-up means comprising a plurality of hold-up members engagable with a workpiece to be sheared, said hold-up members extending longitudinally of said lower blade and being articulatingly connected together in a row so that the hold-up means is able to bend in the longitudinal direction, said hold-up members being disposed at the back of the lower blade to upwardly hold up a work-sheet to be sheared in a manner such that said members are kept upwardly biased and can be moved up and down and can be tilted relative to one another longitudinally of and in compliance with the movements of the upper blade,
• wherein the articulating connection between said hold-up members comprises a horizontal bore formed in one end of each of said hold-up members, a joint block fitting in said bore, and a bolt connecting said joint block to the adjacent hold-up member adjacent said bore.